An embedded touch screen does not need a traditional externally-mounted touch screen, is formed by designing an integrated touch electrode structure at a color filter (CF) side, and can realize the need of lightening and thinning of a display panel. Generally, a touch electrode structure is designed to be provided with longitudinal driving electrodes and transversal sensing electrodes, wherein the sensing electrodes at both sides of each driving electrode are connected by a crossing bridge. Certainly, the positions and the connection modes of the driving electrodes and the sensing electrodes are not limited, the sensing electrodes can be longitudinal and the driving electrodes can be transversal in an electrode structure design, and the driving electrodes at both sides of each sensing electrode are connected by a metal crossing bridge. In addition, patterns of touch electrodes can be various, wherein rhombus is the most basic pattern design in the prior art, but different electrode pattern designs can be selected for realizing different functions.
The specific structure of a liquid crystal display screen of an embedded touch screen in the prior art is as shown in FIG. 1, the liquid crystal display screen mainly includes an upper substrate 12 (namely, color filter (CF) side), a lower substrate 11 (TFT side), and a liquid crystal layer 10 located between the upper substrate 12 and the lower substrate 11, wherein the CF side is integrated with a black matrix 13 (BM), a touch electrode layer 14, a color filter layer 15 (which mainly includes a red color resist (R), a green color resist (G) and a blue color resist (B)), a metal crossing bridge layer 16 (which can also be a transparent oxide crossing bridge) and an over coat layer 17 (OC), respectively. The lower substrate 11 side is mainly integrated with a TFT array structure layer 19 and a transparent pixel electrode (ITO) layer 18 on the TFT array.
As shown in FIG. 2 and FIG. 3, FIG. 3 is an enlarged view of a dotted line box (part A) in FIG. 2, the metal touch electrode layer 14 includes sensing electrodes 141 and driving electrodes 142 which are mutually insulated and located on the same layer, in order to insulate the sensing electrodes 141 from the driving electrodes 142, the sensing electrodes and the driving electrodes are separated to form gaps 1, so as to achieve the insulating purpose. In addition, the metal touch electrode layer 14 is grid-shaped and shielded by the black matrix 13. Generally, the formed gaps are located on the color filter layer, and randomly located on the red color resist (R), the green color resist (G) or the blue color resist (B). As shown in FIG. 1, when a liquid crystal display works, because a light L emitted by a backlight module is irradiated on the metal touch electrode layer 14, the light L is partly reflected on the channels of TFTs on the TFT array structure layer of the lower substrate 11 by the metal touch electrode layer 14 to cause an electricity leakage phenomenon of the TFTs. However, at the gaps 1, due to the absence of the metal touch electrode layer 14, when the light L of a backlight source is irradiated, a light-reflecting phenomenon is very weak, and the reason for this is that there is no any direct reflecting light in a vertical direction, the reflecting phenomenon of the light at an adjacent position in a slanting direction is only in a very small angle range, and the slanting reflected light has no obvious influence on the TFTs which are just opposite to the gaps 1, so that a corresponding TFT off-state current is low. All the TFTs corresponding to the color resists at the gaps 1 are not vertically irradiated by the reflected light, the display effect of the TFTs at the gaps are different from the display effect at non-gap parts, and when the intensity of the backlight source is increased or the TFT off-state current is increased, the patterns of the gaps between the sensing electrodes and the driving electrodes are highlighted on the liquid crystal display screen.